In recent years, radio spectrum resources become increasingly insufficient along with the rapid advancement of mobile communications and the development of other radio applications, so it is necessary to further improve the capacity of a system and the spectrum utilization ratio of the system so as to accommodate a larger number of subscribers and the deployment of new services.
The technology of Multiple-In-Multiple-Out (MIMO) has been widely applied to thereby make it possible to transmit multiple data streams in space. Beamforming can extend a coverage range, improve the quality of a signal, enhance the capability to penetrate through a building and increase the throughput of a subscriber at the edge of a cell due to its definitely directed beam and consequently has been widely applied.
In an existing dual-stream beamforming solution, a channel estimation related matrix is eigen-value decomposed into two sets of eigen-vectors corresponding to the maximum and second maximum eigen-values in a traditional Eigen-value Based Beamforming (EBB) algorithm, and the conjugation of the two eigen-vectors is used as weight coefficients for dual-stream beam forming on a transmit antenna of a base station. A particular flow thereof as illustrated in FIG. 1 includes the following steps:
The step S101 is to perform uplink channel estimation using an uplink pilot to derive a channel matrix H;
The step S102 is channel related matrix R=HHH; and
The step S103 is eigen-value decompose the related matrix into two sets of eigen-vectors corresponding to the maximum and second maximum eigen-values as weight coefficients of antennas.
In this solution, the two eigen-vectors need to be calculated complexly as a result of eigen-value decomposition, and also the eigen-vectors may be determined poorly this way when the uplink pilot is transmitted by a user equipment over the same antenna.